Cyanobacterium-primed Chrysanthemum nursery improves performance of the plant and soil quality

Abstract

The performance of Anabaena laxa–primed nursery of Chrysanthemum cultivar Jaya was evaluated after transplanting into pots fertilised with two different doses of N fertiliser (urea) as full or 75% N, along with full dose of phosphorus (P) and potassium (K) fertilisers. Enhanced N2-fixation activity and, consequently, several fold higher N availability in soil were recorded in such primed nursery cuttings grown with full or 75% N dose, when compared with controls. The values of soil polysaccharides doubled, while microbial biomass C and proteins showed a 10–50% enhancement in the A. laxa–primed treatments, as compared with only fertiliser-amended treatments. The primed plants increased the soil phospholipid fatty acid content by 60% at 100 days after transplanting (DAT), besides recording 20–40% enhancement in plant growth attributes and shoot: root dry weight ratio, as compared with control plants grown with only fertilisers. Enzyme activity in leaves and flowers was enhanced to the tune of one- to fourfold in the A. laxa–primed plants. In terms of quality traits, early appearance of buds and significantly higher amounts of pigments were recorded in A. laxa–primed plants. Soil chlorophyll, available nutrients and root biofilm formation correlated positively with flowering attributes, including flower diameter, dry weight, anthocyanin and carotenoid content of flowers. The novelty of this study was the observed long-term beneficial effects in terms of improved soil microbiological characteristics and plant growth, which lead to better flower quality traits in Chrysanthemum plants, raised using cyanobacterium-primed nursery.